Letter Sequence Other |
---|
|
|
MONTHYEARML0923006082009-09-0303 September 2009 Relief Request WBN2/PDI-4 Related to Ultrasonic Examination of the Reactor Pressure Vessel Shell-To-Flange Welds Project stage: Other 2009-09-03
[Table View] |
|
---|
Category:Letter
MONTHYEARML23319A2452024-01-29029 January 2024 Issuance of Amendment Nos. 366 and 360; 164 and 71 Regarding the Adoption of TSTF-567, Revision 1, Add Containment Sump TS to Address GSI-191 Issues ML24008A2462024-01-18018 January 2024 Revision to the Reactor Vessel Material Surveillance Capsule Withdrawal Schedule CNL-24-017, Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure and Emergency Preparedness Department Procedure Revisions2024-01-17017 January 2024 Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure and Emergency Preparedness Department Procedure Revisions CNL-24-016, Supplement to Application to Modify the Technical Specification Surveillance Requirement 3.9.5.1 (WBN-TS-21-14)2024-01-10010 January 2024 Supplement to Application to Modify the Technical Specification Surveillance Requirement 3.9.5.1 (WBN-TS-21-14) CNL-23-052, Application to Adopt TSTF-427-A, Revision 2, Allowance for Non-Technical Specification Barrier Degradation on Supported System Operability2024-01-0909 January 2024 Application to Adopt TSTF-427-A, Revision 2, Allowance for Non-Technical Specification Barrier Degradation on Supported System Operability CNL-23-062, Application to Revise the Technical Specifications Section 3.8.2, AC Sources-Shutdown, to Remove Reference to the C-S Diesel Generator (WBN-TS-23-018)2024-01-0808 January 2024 Application to Revise the Technical Specifications Section 3.8.2, AC Sources-Shutdown, to Remove Reference to the C-S Diesel Generator (WBN-TS-23-018) ML23346A1382024-01-0303 January 2024 Regulatory Audit Summary Related to Request to Increase the Number of Tritium Producing Burnable Absorber Rods CNL-23-069, Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation2023-12-21021 December 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation IR 05000390/20234412023-12-21021 December 2023 Plantfinal Significance Determination for a Security-Related Greater than Green Finding, Nov, and Assessment Follow-up, 05000390-2023441 and 05000391-2023441-Public CNL-23-036, Application to Revise Function 5 of Technical Specification Table 3.3.2-1, Engineered Safety Feature Actuation System Instrumentation, for the Sequoyah Nuclear Plant and Watts Bar Nuclear Plant (SQN-TS-23-02 and WBN-TS-23-08)2023-12-18018 December 2023 Application to Revise Function 5 of Technical Specification Table 3.3.2-1, Engineered Safety Feature Actuation System Instrumentation, for the Sequoyah Nuclear Plant and Watts Bar Nuclear Plant (SQN-TS-23-02 and WBN-TS-23-08) IR 05000390/20234042023-12-14014 December 2023 Security Baseline Inspection Report 05000390/2023404 and 05000391/2023404 CNL-23-001, Rebaseline of Sections 3.1 and 3.2 of the Technical Specifications (WBN-TS-23-01)2023-12-13013 December 2023 Rebaseline of Sections 3.1 and 3.2 of the Technical Specifications (WBN-TS-23-01) ML23293A0572023-12-0606 December 2023 Issuance of Amendment Nos. 163 and 70 Regarding Adoption of TSTF-501-A, Revision 1, Relocate Stored Fuel Oil and Lube Oil Volume Values to Licensee Control IR 05000390/20230102023-11-30030 November 2023 RE-Issue Watts Bar Nuclear Plant - Biennial Problem Identification and Resolution Inspection Report 050000390/2023010 and 05000391/2023010 and Apparent Violation CNL-23-067, Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2023-11-27027 November 2023 Central Emergency Control Center Emergency Plan Implementing Procedure Revisions IR 05000390/20230032023-11-13013 November 2023 Integrated Inspection Report 05000390/2023003 and 05000391/2023003 and Apparent Violation ML23312A1432023-11-0808 November 2023 Submittal of Dual Unit Updated Final Safety Analysis Report (UFSAR) Amendment 5 CNL-23-059, Supplement to Sequoyah Nuclear Plant, Units 1 and 2, and Watts Bar Nuclear Plant, Units 1 and 2, Application to Revise Technical Specifications to Adopt TSTF-567-A, Revision 1, Add Containment Sump TS to Address GSI-191 Issues (SQN-TS-23-2023-09-20020 September 2023 Supplement to Sequoyah Nuclear Plant, Units 1 and 2, and Watts Bar Nuclear Plant, Units 1 and 2, Application to Revise Technical Specifications to Adopt TSTF-567-A, Revision 1, Add Containment Sump TS to Address GSI-191 Issues (SQN-TS-23-03 CNL-23-061, Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure Revision2023-09-20020 September 2023 Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure Revision ML23251A2002023-09-11011 September 2023 Request for Withholding Information from Public Disclosure for Watts Bar Nuclear Plant, Units 1 and 2 CNL-23-057, Central Emergency Control Center Emergency Plan Implementing Procedure Revisions. Includes CECC-EPIP-1, Revision 76 and CECC-EPIP-9, Revision 642023-09-0505 September 2023 Central Emergency Control Center Emergency Plan Implementing Procedure Revisions. Includes CECC-EPIP-1, Revision 76 and CECC-EPIP-9, Revision 64 IR 05000390/20230052023-08-30030 August 2023 Updated Inspection Plan for Watts Bar Nuclear Plant, Units 1 and 2 - Report 05000390/2023005 and 05000391/2023005 ML23233A0042023-08-28028 August 2023 Proposed Alternative to the Requirements of the ASME Boiler and Pressure Vessel Code for Upper Head Injection Dissimilar Metal Butt Welds IR 05000390/20230022023-08-16016 August 2023 Reissue - Watts Bar Nuclear Plant - Integrated Inspection Report 05000390/2023002 and 05000391/2023002 ML23220A1582023-08-0909 August 2023 Integrated Inspection Report 05000390/2023002 and 05000391/2023002 CNL-23-045, License Amendment Request to Revise Technical Specification Table 1.1-1 Regarding the Required Number of Fully Tensioned Reactor Pressure Vessel Head Closure Bolts (WBN-TS-23-010)2023-08-0707 August 2023 License Amendment Request to Revise Technical Specification Table 1.1-1 Regarding the Required Number of Fully Tensioned Reactor Pressure Vessel Head Closure Bolts (WBN-TS-23-010) CNL-23-028, Application to Revise Technical Specifications to Adopt TSTF-567-A, Revision 1, Add Containment Sump TS to Address GSI-191 Issues (SQN-TS-23-03 and WBN-TS-23-06)2023-08-0202 August 2023 Application to Revise Technical Specifications to Adopt TSTF-567-A, Revision 1, Add Containment Sump TS to Address GSI-191 Issues (SQN-TS-23-03 and WBN-TS-23-06) ML23192A4472023-07-31031 July 2023 Staff Assessment of Updated Seismic Hazards at TVA Sites Following the NRC Process for the Ongoing Assessment of Natural Hazards Information CNL-23-055, Tennessee Valley Authority - Emergency Preparedness Department Procedure Revision. Includes EPDP-3, Revision 3, Emergency Plan Exercises and Preparedness Drills2023-07-25025 July 2023 Tennessee Valley Authority - Emergency Preparedness Department Procedure Revision. Includes EPDP-3, Revision 3, Emergency Plan Exercises and Preparedness Drills IR 05000390/20230112023-07-24024 July 2023 Quadrennial Focused Engineering Inspection (FEI) Commercial Grade Dedication Report 05000390 2023011 and 05000391 2023011 CNL-23-053, Tennessee Valley Authority - Radiological Emergency Plan Revisions2023-07-18018 July 2023 Tennessee Valley Authority - Radiological Emergency Plan Revisions CNL-23-020, Application to Revise Technical Specifications to Adopt TSTF-501-A, Revision 1, Relocate Stored Fuel Oil and Lube Oil Volume Values to Licensee Control (WBN-TS-22-06)2023-06-28028 June 2023 Application to Revise Technical Specifications to Adopt TSTF-501-A, Revision 1, Relocate Stored Fuel Oil and Lube Oil Volume Values to Licensee Control (WBN-TS-22-06) CNL-23-049, Tennessee Valley Authority - Radiological Emergency Plan and Central Emergency Control Center Emergency Plan .2023-06-26026 June 2023 Tennessee Valley Authority - Radiological Emergency Plan and Central Emergency Control Center Emergency Plan . ML23122A2322023-06-0707 June 2023 Issuance of Amendment Nos. 162 and 69 Regarding Change to Date in Footnotes for Technical Specification 3.7.11, Control Room Emergency Air Temperature Control System (Creatcs) CNL-23-044, Transmittal of Revision 3 to WCAP-18774-P and WCAP-18774-NP, Addendum to the Rotterdam Dockyard Company Final Stress Report for 173 P.W.R. Vessels TVA III & IV (Report No. 30749-B-030, Rev. 3) - Evaluation of One Closure Stud Out2023-06-0101 June 2023 Transmittal of Revision 3 to WCAP-18774-P and WCAP-18774-NP, Addendum to the Rotterdam Dockyard Company Final Stress Report for 173 P.W.R. Vessels TVA III & IV (Report No. 30749-B-030, Rev. 3) - Evaluation of One Closure Stud Out IR 05000390/20234032023-05-30030 May 2023 Cyber Security Inspection Report 05000390/2023403 and 05000391/2023403 ML23131A1812023-05-23023 May 2023 Correction to Amendment No. 161 to Facility Operating License No. NPF-90 CNL-23-042, Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2023-05-16016 May 2023 Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revisions IR 05000390/20220032023-05-0909 May 2023 Reissue Watts Bar Nuclear Plant - Integrated Inspection Report 05000390/2022003 and 05000391/2022003 ML23125A2202023-05-0505 May 2023 Issuance of Amendment No. 161 Regarding a Change to Footnotes for Technical Specification Table 1.1-1 Modes (Emergency Circumstances) IR 05000390/20230012023-05-0404 May 2023 Integrated Inspection Report 05000390/2023001 and 05000391/2023001 CNL-23-043, Emergency License Amendment Request to Relax the Required Number of Fully Tensioned Reactor Pressure Vessel Head Closure Studs in Technical Specification Table 1.1-1, Modes (WBN-TS-23-09)2023-05-0404 May 2023 Emergency License Amendment Request to Relax the Required Number of Fully Tensioned Reactor Pressure Vessel Head Closure Studs in Technical Specification Table 1.1-1, Modes (WBN-TS-23-09) CNL-23-032, Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Unit 1 and 2, Nuclear Quality Assurance Plan, TVA-NQA-PLN89-A, Revision 412023-04-27027 April 2023 Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Unit 1 and 2, Nuclear Quality Assurance Plan, TVA-NQA-PLN89-A, Revision 41 CNL-23-030, Tennessee Valley Authority - Hydrologic Engineering Center River Analysis System Project Milestone Status Update2023-04-27027 April 2023 Tennessee Valley Authority - Hydrologic Engineering Center River Analysis System Project Milestone Status Update CNL-23-033, Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revision2023-04-24024 April 2023 Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revision CNL-23-029, Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2023-04-11011 April 2023 Radiological Emergency Plan and Central Emergency Control Center Emergency Plan Implementing Procedure Revisions ML23072A0652023-04-0505 April 2023 Units 1 and 2 Issuance of Amendment Nos. 364 and 358; 160 and 68 Regarding a Revision to Technical Specification 3.4.12 ML23073A2762023-04-0303 April 2023 Individual Notice of Consideration of Issuance of Amendments to Facility Operating Licenses, Proposed No Significant Hazards Consideration Determination, and Opportunity for a Hearing (EPID L-2023-LLA-0029) (Letter) CNL-23-023, Annual Insurance Status Report2023-03-30030 March 2023 Annual Insurance Status Report CNL-23-024, TVA Guarantee of Payment of Deferred Premiums - 2022 Annual Report2023-03-29029 March 2023 TVA Guarantee of Payment of Deferred Premiums - 2022 Annual Report 2024-01-09
[Table view] Category:Safety Evaluation
MONTHYEARML23319A2452024-01-29029 January 2024 Issuance of Amendment Nos. 366 and 360; 164 and 71 Regarding the Adoption of TSTF-567, Revision 1, Add Containment Sump TS to Address GSI-191 Issues ML23293A0572023-12-0606 December 2023 Issuance of Amendment Nos. 163 and 70 Regarding Adoption of TSTF-501-A, Revision 1, Relocate Stored Fuel Oil and Lube Oil Volume Values to Licensee Control ML23233A0042023-08-28028 August 2023 Proposed Alternative to the Requirements of the ASME Boiler and Pressure Vessel Code for Upper Head Injection Dissimilar Metal Butt Welds ML23125A2202023-05-0505 May 2023 Issuance of Amendment No. 161 Regarding a Change to Footnotes for Technical Specification Table 1.1-1 Modes (Emergency Circumstances) ML23072A0652023-04-0505 April 2023 Units 1 and 2 Issuance of Amendment Nos. 364 and 358; 160 and 68 Regarding a Revision to Technical Specification 3.4.12 ML23048A3042023-03-0808 March 2023 Tennessee Valley Authority - Request for Relief from Requirements of ASME Boiler and Pressure Vessel Code Regarding Weld Examination Coverage (EPID L-2022-LLR-0045,-0046,-0047) ML22348A0052023-01-25025 January 2023 Issuance of Amendment Nos. 326, 349, and 309; 363 and 35; 159 and 67 Regarding Adoption of TSTF-554, Revise Reactor Coolant Leakage Requirements ML22349A6472023-01-20020 January 2023 Issuance of Amendment Nos. 325, 348, and 308; 362 and 356; and 158 and 66 Regarding Adoption of TSTF-529, Rev. 4, Clarify Use and Application Rules ML22271A9142022-12-0707 December 2022 Issuance of Amendment Nos. 324, 347, and 307; 360 and 354; 157 and 65 Regarding a Revision to the Emergency Action Level Scheme ML22293A4082022-11-14014 November 2022 Revision to the Reactor Vessel Material Surveillance Capsule Withdrawal Schedule ML22257A0512022-11-0404 November 2022 Issuance of Amendment Nos. 156 and 64 Regarding Adoption of TSTF-205-A, Revision 3, and TSTF-563-A ML22276A1612022-10-24024 October 2022 Issuance of Amendment Nos. 359, 353, 155, & 63 Regarding Adoption of TSTF Traveler TSTF-577, Revised Frequencies for Steam Generator Tube Inspections ML22272A5682022-10-12012 October 2022 Authorization of Alternatives to Certain Inservice Testing Requirements in the American Society of Mechanical Engineers Operating and Maintenance Code ML22187A0192022-09-20020 September 2022 Issuance of Amendment No. 154 Regarding Revision to Technical Specification 3.3.2 to Revise Allowable Value for Trip of Turbine-Driven Main Feedwater Pumps ML22187A1812022-09-20020 September 2022 Issuance of Amendment Nos. 153 and 62 Regarding Extension of Completion Time for Technical Specification 3.7.8 for Inoperable Essential Raw Cooling Water Train ML22014A2062022-05-0404 May 2022 Issuance of Amendment Nos. 152 and 61 Regarding Revision to Technical Specifications to Delete a Redundant Unit of Measure for Certain Radiation Monitors ML22084A0012022-04-0505 April 2022 Clinch River Nuclear Site; Sequoyah Nuclear Plant, Units 1 and 2; Watts Bar Nuclear Plant, Units 1 and 2, Review of Quality Assurance Plan Changes ML22070A0022022-03-28028 March 2022 Review of the Fall 2021 Mid Cycle Generic Letter 95-05 Voltage-Based Alternate Repair Criteria Report ML21306A2872022-01-25025 January 2022 Issuance of Amendment No. 60 Regarding Revision of Technical Specification Requirements Specific to the Model D3 Steam Generators That Will No Longer Apply Following Steam Generator Replacement ML21334A2952022-01-18018 January 2022 Issuance of Amendment No. 151 Regarding Revision to TS 3.7.12 for One-Time Exception to Permit Continuous Opening of Auxiliary Building Secondary Containment Enclosure During Unit 2 Steam Generator Replacement ML21334A3892022-01-12012 January 2022 Issuance of Amendment No. 59 Regarding Revision to Steam Generator Tube Rupture Dose Analysis ML21271A1372021-12-16016 December 2021 Issuance of Amendment Nos. 150 and 58 Regarding Modification of Technical Specification Surveillance Requirement 3.6.15.4, Shield Building ML21260A2102021-11-22022 November 2021 Issuance of Amendment No. 57 to Revise Technical Specifications to Change the Steam Generator Secondary Side Water Level ML21189A3072021-11-0303 November 2021 Issuance of Amendment Nos. 149 and 56 Regarding Modification of Technical Specification 5.7.2.19, Containment Leakage Rate Testing Program ML21158A2842021-09-17017 September 2021 Issuance of Amendment Nos. 148 and 55 to Revise Technical Specifications for Function 6.E of Table 3.3.2-1, Engineered Safety Feature Actuation System Instrumentation ML21153A0492021-07-26026 July 2021 Issuance of Amendment No. 147 Regarding Change to Steam Generator Tube Inspection Frequency and Adoption of Technical Specification Task Force (TSTF) Traveler TSTF-510 ML21161A2392021-06-24024 June 2021 Issuance of Amendment No. 54 Regarding Use of Temperature Adjustment to Voltage Growth Rate for the Generic Letter 95-05 Steam Generator Tube Repair Criteria ML21148A1002021-06-17017 June 2021 Issuance of Amendment No. 53 Regarding Neutron Fluence Calculation Methodology ML21099A2462021-05-14014 May 2021 Issuance of Amendment Nos. 146 and 52 to Adopt TSTF-490, Deletion of E Bar Definition and Revision to RCS Specific Activity Tech Spec ML21130A6012021-05-13013 May 2021 Correction of Proposed Alternative IST-RR-8 to the Requirements of the ASME OM Code for the Residual Heat Removal Pump 1B-B ML21078A4842021-05-0505 May 2021 Issuance of Amendment Nos. 145 and 51 for One-Time Change to Technical Specification 3.7.11 to Extend the Completion Time for Main Control Room Chiller Modifications ML21110A0372021-04-29029 April 2021 Proposed Alternative IST-RR-8 to the Requirements of the ASME OM Code for the Residual Heat Removal Pump 1B-B ML21064A4082021-03-10010 March 2021 Correction of Safety Evaluation for License Amendment Nos. 143 and 50 (EPID L-2020-LLA-0005) (Non-Proprietary) ML21015A0342021-03-0909 March 2021 Issuance of Amendment No. 144 Regarding Post Accident Monitoring Instrumentation ML21034A1692021-02-26026 February 2021 Issuance of Amendment Nos. 143 and 50 Regarding Implementation of Full Spectrumtm Loss-of-Coolant Accident Analysis (LOCA) and New LOCA-Specific Tritium Producing Burnable Absorber Rod Stress Analysis Methodology ML20232C6222021-02-11011 February 2021 Issuance of Amendment Nos. 142 and 49 Regarding Revision to Technical Specifications to Implement WCAP-17661-P-A, Revision 1, Improved RAOC and CAOC Fq Surveillance Technical Specifications (EPID L-2020-LLA-0037 ML21027A1672021-02-0909 February 2021 Issuance of Amendment No. 48 Regarding Use of Alternate Probability of Detection Values for Beginning of Cycle in Support of Operational Assessment ML20350B4932021-01-25025 January 2021 Issuance of Amendment Nos. 352, 346, 141, and 47 Regarding the Adoption of Technical Specification Task Force Traveler, TSTF-569, Revision 2, Revise Response Time Testing Definition ML20268A0822021-01-12012 January 2021 Issuance of Amendment Nos. 314, 337, and 297; 351 and 345; 140 and 46 Regarding Changes to the Technical Specifications ML20245E4132020-12-0808 December 2020 Issuance of Amendment Nos. 139 and 45 Regarding Revisions to Technical Specification 3.6.15, Shield Building ML20282A3452020-11-19019 November 2020 Issuance of Amendment Nos. 313, 336, 296, 350, 344, 138, and 44 Revise Emergency Plan On-Shift Emergency Medical Technician & Onsite Ambulance Requirements ML20239A7912020-10-28028 October 2020 Issuance of Amendment Nos. 137 and 43 Regarding Revision to Technical Specifications to Adopt Technical Specification Task Force Traveler 541, Revision 2 ML20226A4442020-10-21021 October 2020 Issuance of Amendment No. 42 Regarding Measurement Uncertainty Recapture Power Uprate ML20167A1482020-08-19019 August 2020 Issuance of Amendment Nos. 136 and 41 Regarding the Automatic Transfer from a Unit Service Station Transformer to a Common Station Service Transformer ML20156A0182020-08-10010 August 2020 Issuance of Amendment No. 40 Regarding Technical Specifications for Steam Generator Tube Repair Sleeve ML20076A1942020-04-30030 April 2020 Issuance of Amendment Nos. 134 and 38 Regarding Adopting the Title 10 CFR Section 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Plants ML20057E2422020-03-30030 March 2020 Issuance of Amendment Nos. 133 and 37 Regarding Changes to Technical Specifications Pertaining to Diesel Generator Start Instrumentation (EPID-L-2020-LLA-0003) ML20028F7332020-02-28028 February 2020 Issuance of Amendment Nos. 132 and 36 Regarding the Adoption of Technical Specifications Task Force Traveler TSTF-425, Revision 3 ML20024F8352020-02-24024 February 2020 Issuance of Amendment No. 35 Regarding One-Time Extension of Completion Time for Technical Specification 3.7.8 for Inoperable Essential Raw Cooling Water Train ML19336C5192019-12-10010 December 2019 Issuance of Amendment Nos. 131 and 34 Regarding Correction to Unbalanced Voltage Relay Instrumentation Values 2024-01-29
[Table view] |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 September 3, 2009 Mr. Ashok S. Bhatnagar Senior Vice President, Nuclear Generation Development and Construction Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801
SUBJECT:
WATTS BAR NUCLEAR PLANT, UNIT 2 - RELIEF REQUEST WBN-2/PDI-4 RELATED TO ULTRASONIC EXAMINATION OF THE REACTOR PRESSURE VESSEL SHELL-TO-FLANGE WELDS (TAC NO. ME0022)
Dear Mr. Bhatnagar:
By letter dated October 30,2008, Tennessee Valley Authority (TVA) submitted Relief Request WBN-2/PDI-4, which proposes an alternative to the requirements of American Society of Mechanical Engineers Boiler and Pressure Vessel Code,Section XI, paragraph IWA-2232 of the 2001 Edition through the 2003 Addenda, for the Preservice Inspection Program at Watts Bar Nuclear Plant, Unit 2. Specifically, TVA proposed the use of Appendix VIII and Performance Demonstration Initiative for examination of the reactor pressure vessel shell-to-flange welds in lieu of the requirements of Appendix I and the associated Article 4 of ASME Code Section V.
, The Nuclear Regulatory Commission staff has completed its review of the subject relief request.
.The staff finds that TVA's proposed alternative provides an acceptable level of quality and safety. Therefore, pursuant to 10 CFR 50.55a(a)(3)(i), the alternative proposed in Relief Request WBN-2/PDI-4 is authorized for the performance of the Preservice Inspection Program at Watts Bar Nuclear Plant, Unit 2. The staff's evaluation and conclusions are contained in the enclosed safety evaluation.
If you have any questions regarding this matter, please contact Joel S. Wiebe at 301-415-6606 or via e-mail at JoeI.Wiebe@nrc.gov.
Sincerely, LilL L. RaghaVa~ief Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No: 50-391
Enclosure:
Safety Evaluation cc w/encl: Distribution via Listserv
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REQUEST FOR APPROVAL OF RELIEF REQUEST WBN-2/PDI-4 REGARDING USE OF APPENDIX VIII WATTS BAR NUCLEAR PLANT, UNIT 2 TENNESSEE VALLEY AUTHORITY DOCKET NO. 50-391
1.0 INTRODUCTION
By letter dated October 30,2008, Tennessee Valley Authority (TVA) requested, pursuant to Section 50.55a(a)(3)(i) of Part 50 of Title 10 of the Code of Federal Regulations (10 CFR),
approval of Relief Request (RR) WBN-2/PDI-4, which proposes an alternative to the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),Section XI, paragraph IWA-2232 of the ASME Section XI 2001 Edition through the 2003 Addenda.
Specifically, in RR WBN-2/PDI-4, TVA proposes to use the requirements of Appendix VIII and Performance Demonstration Initiative (PDI) for examination of the reactor pressure vessel shell*
to-flange welds in lieu of the requirements of Appendix I and the associated Article 4 of ASME Code Section V for the Preservice Inspection (PSI) Program at Watts Bar Nuclear Plant, Unit 2 (WBI'J-2).
2.0 REGULATORY EVALUATION
The regulations in 10 CFR 50.55a(g)(2) specify that for a boiling or pressurized water-cooled nuclear power facilities whose construction permit was issued on or after January 1, 1971, but before July 1, 1974, components (including supports) which are classified as ASME Code Class 1 and 2 must be designed and be provided with access to enable the performance of inservice examination of such components (including supports) and must meet the preservice examination requirements of ASME Section XI. As stated in 10 CFR 50.55a(a)(3), alternatives to the requirements of paragraph (g) may be used, when authorized by the Nuclear Regulatory Commission (NRC), if (i) the proposed alternatives would provide an acceptable level of quality and safety or (ii) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. It is stated in 10 CFR 50.55a(g)(5)(iii) that if the licensee has determined that conformance with certain code requirements is impractical for its facility, the licensee shall notify the Commission and submit information, as specified in 10 CFR 50.4, to support the determinations.
Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2, and 3 components (including supports) shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, "Rules for Inservice Inspection of Nuclear Power Plant Components," to the extent practical within the limitations of design, geometry, and materials of construction of components. The regulations require that inservice examination of components and system pressure tests conducted during Enclosure
-2 the first 1O-year interval and subsequent intervals comply with the requirements of the latest edition and addenda of Section XI of the ASME Code incorporated by reference in 10 CFR 50.55a(b) 12 months prior to the start of the 120-month interval, subject to the limitations and modifications listed therein. The applicable code of record for the preservice examinations at WBN-2 is the ASME Code,Section XI, 2001 Edition through the 2003 Addenda. The proposed RR is sought for the performance of the WBN-2 PSI Program. The information provided by the licensee in support of the request has been evaluated by the NRC staff and the bases for disposition are documented below.
3.0 TECHNICAL EVALUATION
3.1 Affected Components ASME Code Class 1 Reactor Pressure Vessel (RPV) Upper Vessel Shell-to-Flange Welds, Table IWB-2500-1 Category B-A, Item Number B1.30.
3.2 Applicable Code Requirements In accordance with ASME Code,Section XI, Table IWB-2500-1 Category B-A, Item Number B1.30, upper vessel shell-to-flange welds require a vOlumetric examination of essentially 100 percent of the weld length. In addition, ASME Code,Section XI, Paragraph IWA-2232 states that: "Ultrasonic examinations shall be conducted in accordance with Appendix I."
Further, ASME Code,Section XI, Appendix I, Paragraph 1-2110 (b) states that: "Ultrasonic examination of reactor vessel-to-flange welds, closure head-to-flange welds, and integral attachment welds shall be conducted in accordance with Article 4 of Section V, except that alternative examination beam angles may be used."
3.3 Proposed Alternative TVA proposed as an alternative "to use the procedures, personnel, and equipment qualified to meet the requirements of ASME Code,Section XI, Appendix VIII, Supplements 4 and 6 as administered by the Electric Power Research Institute's POI to conduct the required vessel-to-flange weld examinations."
3.4 TVA's Basis for the Alternative Use of the Appendix VIII/POI processes would enhance the quality of the examination results reported because the detection sensitivity is more conservative and the procedure requires the examiner to evaluate all indications determined to be flaws regardless of their associated signal amplitude. Procedures, equipment, and personnel qualified through the Appendix VIII, Supplements 4 and 6 POI programs have shown to have a high probability of detection of flaws and are generally considered superior to the techniques employed earlier for RPV examinations, resulting in increased reliability of RPV inspections.
3.5 NRC Staff Evaluation TVA has proposed to examine the RPV flange-to-upper shell weld from the reactor vessel inside surface by using procedures, equipment, and personnel qualified by POI. TVA will use remote mechanized equipment to examine the reactor vessel flange-to-shell weld from the inside
- 3 surface in accordance with the POI requirements. In September 1999, 10 CFR 50.55a was issued and required an expedited implementation of the 1995 Edition with 1996 Addenda, ASME Code,Section XI, Appendix VIII supplements in accordance with specific dates and specific components to be examined. The RPV flange-to-upper shell weld was not included in the September 1999 10 CFR 50.55a POI requirements.
Supplement 4 to Appendix VIII provides requirements for qualification of examinations of the cladding to base metal interface of the reactor vessel. Supplement 6 to Appendix VIII provides requirements for qualification of reactor vessel welds other than the cladding to base metal interface for reactor vessels. These POI-qualified procedures are technically superior to the previous ASME Code,Section V, Article 4 methodologies that are amplitude based. The POI examinations are more sensitive to identifying flaws, because the examination sensitivity levels, detailed procedure criteria, and blind demonstrations enhance or verify their effectiveness. Prior to implementing POI examinations volumetric examinations in accordance with ASME Code,Section V were conducted at the less sensitive level of 50 percent distance amplitude correction curve (OAC) for flaws located in the outer 80 percent of the material thickness and 20 percent OAC for flaws located from the clad-base metal interface to a depth of about 20 percent of the material thickness. In addition the POI qualified procedures provide a higher level of flaw probability of detection because all signals are interpreted as flaws and are not dependent on minimum amplitude response. All indications will be measured and assessed in accordance with the applicable criteria.
The NRC staff determined that the licensee's proposed alternative to use the ASME Code,Section XI, Appendix VIII examination requirements in the performance of the reactor vessel inside surface volumetric examination surpasses the quality of the examination techniques specified by Section V of the ASME Code. Therefore, TVA's proposed alternative provides an acceptable level of quality and safety of the RPV flange-to-upper shell weld.
4.0 CONCLUSION
The NRC staff has reviewed TVA's proposed RR WBN-2/POI-4 submittal and concludes that the proposed alternative provides an acceptable level of quality and safety and is authorized, pursuant to 10 CFR 50.55a(a)(3)(i), for the performance of Preservice Inspection Program at Watts Bar Nuclear Plant, Unit 2. All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in the subject requests for relief remain applicable, including third-party review by the authorized Nuclear Inservice Inspector.
Principle Contributor: K. Hoffman Date: September 3, 2009